Consisting of five 5-minute episodes, the series will launch on the ITV Primeval website on December 22.
Set in the period between the third and fourth series, the webisodes will introduce new characters Philip Burton (Alexander Siddig), Matt (Ciaran McMenamin) and Jess (Ruth Kearney), while giving fans their first glimpse at the new ARC facility.
Ben Freeman, senior editor for soaps and drama at ITV.com, said: "We are delighted to be working with Impossible Pictures to offer fans of the show this new strand of thrilling content that builds on the excitement in the show.”
The show's co-creator Tim Haines added: "We are delighted that ITV.com will be showing this unique content as it will not only help viewers connect the end of series three with the start of series four, but it will also give our loyal fans 15 minutes of thrilling new visual material that will whet their appetites in advance of the start of the new season of the series."
The new series of Primeval begins on January 1 on ITV1.